Foam Board Insulation Attic Rafters

By adding the insulation under the rafters to maintain a ventilated roof at a cost of say1600 for a r28 airsealed radiant barrier product with the ability to add more if needed at a later date how is that a bad idea if an air sealed attic floor w blown in will cost roughly the same and i still won t have a good environment for hvac etc.

Foam board insulation attic rafters.

Often the r value of fiberglass insulation is too low and requires the rafters to be retrofitted making foam board a better choice. Some types of thicker foam board insulation are available but they may need to be special ordered. A brief snippet of how and why i used rigid foam insulation for some areas of the tiny house. Measure the length and width between two rafters in your attic and transfer the measurements to a 4 ft by 8 ft of rigid foam insulation board.

R 7 5 scored squared edge rigid foam board insulation sheathing model 88wd view the owens corning exterior insulation 17 74 17 74. Polyurethane or polystyrene spray foams can provide thorough coverage to roof rafters and attic walls in much less time than is needed for other materials. It comes in standard size 4 8 sheets and smaller sizes in many different thicknesses from 1 4 inch to 2 inches. It s worth changing tactics to insulate between the rafters and wall joists instead of the floor.

2 snap a chalk line between the length measurements. Foam board insulation is easy to use and is a great diy way to add some insulation. When building my current home i was faced with a dilemma on how to insulate a bonus room that would be upstairs. Affix rigid foam insulation to the attic side of the hatch or door.

You can use rigid foam panels or do as. Unlike solid insulation products that require careful measurement cutting and fitting spray foam can cover even the most uneven surface instantly. The superattic system utilizes proprietary silverglo rigid foam insulation panels to fully seal and insulate the attic directly beneath the roof rafters and directly inside the gable ends. Better than spray foam thermal break and relatively consistent r 30.

Attic 7 basement 12 ceiling insulation 8 crawlspace 6 exterior sheathing 13 exterior wall foundation 17 exterior wall 4 floor 2 garage 9. Add weatherstripping around the perimeter and a sweep to the door of a walk up attic. Attic hatch or door. Pull down stair or ladder.